Lithographic resolution

Nanoscale lithographic resolution, approaches to, 15 186-189 Nanoscale materials preparing, 24 61 properties od, 17 45 Nanoscale modules, production of, 26 786-787... 

The resist exhibits very high resolution and is well within the lithographic resolution capability of conventional exposure tools such as the g-line or i-line steppers in use today. 

Chemical mechanical jwlishing (CMP) has been widely accepted for oxide and metal layer planarization to eliminate step coverage concerns and improve lithographic resolution. Tungsten (W) CMP is used to remove the excess W deposited by nonselective chemical vapx>r deposition (CVD) for the formation of vias in IC multilevel interconnects. 

Combination of a pulsed bias and noncontact AFM has been found to improve the control of the writing process [78]. This method reduces the tip-substrate interaction time and thus improves the reliability and lithographic resolution. The frequency of oscillation and the field pulsing frequencies need to be adjusted to create a definite phase relation between the two and it was found that the minimum line width is obtained when the applied field is on during the time the cantilever tip is furthest from the substrate. The process also needs adjustment of the duty cycle. 

In the case of ionic polymerizations, (e. g. CROP of oxetanes), under the conditions used for fabrication of OLED devices (inert gas atmosphere), there is no explicit termination step. Thus in the end of the polymerization, the chain ends remain positively charged. This could lead to a reduced lithographic resolution (and blurring of the image). 

A very simple method to test the lithographic resolution of a material is to use TEM grids (TEM = transmission electron microscopy) as a contact-shadow masks [57]. AFM investigations of crosslinked layers, structured by using the method described above, show, that the used grids have been nicely reproduced. 

The second focus of this chapter is the full-color capability. The combination with the crosslinking strategy led to a novel class of semiconductive materials smart (negative) photoresists. In addition to the fabrication of multilayer structures the layers could be simply patterned laterally by the use of a photolithographic process. In the few cases where the lithographic resolution was tested, it was easily sufficient for RGB pixilated deposition. In addition, these materials come with additional new features ( added values ). 

The above-mentioned resist classification based on radiation sources/expo-sure wavelength is the reflection of the industry s quest for higher resolution. The lithographic resolution (R) is proportional to the exposing wavelength (A) and inversely proportional to the numerical aperture (NA) of the lens (Rayleigh s equation) ... 

The single-exposure techniques are based on the lithographic resolution R... 

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